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Comment by infogulch | Hacker News Reader

That's the crux of the problem. You have to build for maximum capacity, even though that happens comparatively very rarely. The electric grid faces the same problem, perhaps worse.

I remember an enlightening graph of power grid demand over a year sorted by demand. (Which I can't find for the life of me.) The vast majority of the time is spent very near the average, but a very small amount of time needs almost twice the average, and another very small amount of time demands half the average. The problem is, the grid must be big enough to supply that 3-times-a-year double the average demand, which just sits there idly the rest of the year.

I imagine demand for transportation is similar though not as exaggerated.

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There's no reason the grid must accommodate peak demand. Two other options are simple failure to meet demand (you only get 10 amps) and dynamic pricing to reduce demand (if air conditioning costs $100/hr you might not use it).

That would work if personal/residential consumption used the majority of power production but industrial and transportation uses far outpace the demand of consumers: http://www.nap.edu/books/12621/xhtml/images/p2001b2d5g186001...

The costs associated with throttling/halting these sectors far outweighs the cost of overbuilt infrastructure. Electricity is already sold by the megawatt in "day ahead" commodity form so businesses have already priced this information into the market.

That chart is misleading because it shows consumption of all sources of energy, not just electricity. We don't use 28% of our electricity for transportation (yet!). Listings of electricity consumption by sector [1] show that the residential sector consumes the biggest share of electricity in the US. And the residential sector also has the highest seasonal variability in power consumption [2]. So better demand control for consumers might actually pay off pretty well.

[1] http://en.wikipedia.org/wiki/Electric_energy_consumption#Ele... [2] http://www.eia.gov/todayinenergy/detail.cfm?id=10211

Bingo. If getting to work at 9 AM costs me five times more than getting to work at 7, you can be sure I'll figure out a way to do the latter. Motivating large chunks of the population to think about rush hour would be a "good thing".

What if you are a fireman and you need to get to your shift? Can those burning people wait?

Can everyone dynamically shift business routines due to "demand"?

> What if you are a fireman and you need to get to your shift? Can those burning people wait?

There's no particular reason emergency service shift changes need to be synced to the common business day -- indeed, my intuition would be that accident timing patterns would make this a bad idea independent of traffic impacts -- but there's also no reason that employers with employees for which they have strong fixed-time needs couldn't subsidize (or, in the case of public necessity where the employer is the government, exempt) their employees traffic fees.

> Can everyone dynamically shift business routines due to "demand"?

Yes, they can -- but, of course, there is a cost (which varies from situation to situation) in doing so. Of course, there's also a cost -- particularly an externalized cost born by others -- of traffic. If you effectively internalize the external cost (i.e., make it born by the people making the decision to engage in the action), then behavior should reflect the true costs and benefits resulting from the action.

Great! I'll just drop my kids off outside the school gate on the way in at 7.15 and hope the teacher decided to opt for an early commute in today too.

Most schools around me start at ~7:30 and are open for an hour or so earlier in case the kids want to eat breakfast.

A friend of mine works in energy and once said "If roads catered for traffic the way power networks cater for power demand, the Sydney Harbour Bridge would be 100 lanes wide."

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